1. Field of the Invention
The present invention relates generally to video and, more specifically, to video filtering.
2. Description of the Related Art
A video image may be displayed on a display using multiple Picture Elements (pixels). The number of possible shades for a pixel on the display may depend, in part, on the number of bits used for each pixel. For example, if 8 bits are used for each pixel, the pixel may have one of 256 (2^8) possible colors or shades of gray.
Each frame in a series of video frames (e.g., captured using a camera in a video conference) may include several pixels. Image elements with relatively no movement, such as the background, may have pixel values that stay fairly constant between each frame (e.g., the pixels representing the image element may not change very much between frames in a series of frames). Ideally, if the camera is still, and an object in the camera's field of view is not moving, the pixel values in the respective portions of the video frames in the series may be identical. However, noise (e.g., from different electronic sources, camera jitter, etc.), may cause pixels for non-moving objects to have different values between frames (noise may also affect the values of moving object pixels as well).
When transmitting and/or displaying the frames in series, the previous frame's pixel values (for pixels that are not moving) may be kept without needing to refresh their values. The transmission bandwidth for video frames may then be focused on transmitting moving pixels (or vectors representing changing values for a series of pixels). However, with noise, it may be difficult to determine which fluctuations are due to movement and which are due to noise. These fluctuations may need to be filtered.